stable-rc 6.1: x86: clang build failed - block/blk-cgroup.c:1237:6: error: variable 'ret' is used uninitialized whenever 'if' condition is true

[Naresh Kamboju]

Linux stable-rc 6.1 build failed x86 and i386 with clang.

Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>

Build log:
-----------
block/blk-cgroup.c:1237:6: error: variable 'ret' is used uninitialized
whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
        if (init_blkcg_llists(blkcg))
            ^~~~~~~~~~~~~~~~~~~~~~~~
block/blk-cgroup.c:1287:9: note: uninitialized use occurs here
        return ret;
               ^~~
block/blk-cgroup.c:1237:2: note: remove the 'if' if its condition is
always false
        if (init_blkcg_llists(blkcg))
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
block/blk-cgroup.c:1222:33: note: initialize the variable 'ret' to
silence this warning
        struct cgroup_subsys_state *ret;
                                       ^
                                        = NULL
1 error generated.

Links,
 - https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-6.1.y-sanity/build/v6.1.38-599-g5071846d06ef/testrun/18327562/suite/build/test/clang-lkftconfig/history/
 - https://storage.tuxsuite.com/public/linaro/lkft/builds/2SfFoWj9NmKWHRijR0hcoXGjLhr/

 tuxmake \
 --runtime podman --target-arch x86_64 \
 --toolchain clang-16 \
 --kconfig https://storage.tuxsuite.com/public/linaro/lkft/builds/2SfFoWj9NmKWHRijR0hcoXGjLhr/config
\
 LLVM=1 LLVM_IAS=1

--
Linaro LKFT
https://lkft.linaro.org